Container and Closure Assembly

ABSTRACT

A container and closure assembly is provided. A projecting rim surrounds an opening into the container and includes a rim sealing surface. The closure is provided for covering the container opening. The closure is formed from a support ring dimensioned to surround the rim of the container and a sealing membrane. The ring includes a ring sealing surface positioned concentric with the rim sealing surface. The membrane is sealed to the rim sealing surface and further sealed to the ring sealing surface. The seal of the membrane to the rim sealing surface is separable upon removal of the ring from its position surrounding the rim of the container, while the seal of the membrane to the ring remains in place upon ring removal.

FIELD OF THE INVENTION

The present disclosure relates to container and closure assembly.Preferably, the closure forms a hermetic seal with the container, withthe seal being removable and the closure being replaceable on thecontainer.

BACKGROUND

Closures in the form of a lid or overcap for a container are provided ina number of forms. An example of a container with a flat sealing rim anda plastic overcap is shown in U.S. Pat. No. 7,165,306. Means forhermetically sealing a container in conjunction with the reclosable lidor overcap are also known. One example of a hermetic seal for acontainer is the provision of a flexible membrane sealed to the rim ofthe container, with the membrane being removable to provide access tothe contents of the container.

U.S. Pat. No. 4,171,084 to Smith shows a closure for a container havingan outer ring with a central opening that is closed by a laminate sheet.The ring includes an upper circular portion and vertically positionedskirt portion. The two portions surround the top and outside edge of therim of the container. The laminate sheet is secured between the bottomsurface of the upper ring portion and the upper edge of the containerrim. The laminate is sealed to both the ring and container rim byinduction heating. Opening the container by removal of the ring causes aseparation of the laminate from the rim of the container.

U.S. Pat. No. 4,359,169 to Helms et al shows a closure for a containerhaving a membrane sealed between the underside surface of the outerperipheral edge of the closure and the top surface of the rim of thecontainer. The closure includes a pivotable inner member surrounded byan outer ring member. The pivotable member includes a rim having adownwardly projecting flange that is sealed to the membrane. As thepivotable member is lifted, the membrane tears adjacent the flange and acentral portion of the membrane is carried by the member.

U.S. Pat. No. 3,892,351 and U.S. Pat. No. 3,973,719 to Johnson et alshow a container with a membrane seal attached to the upper surface ofthe container rim. An overcap is provided on an underside surface with apattern of heat deformable ribs that engage the edge of the membrane inthe area of the container rim. An RF source is used to heat a conductiveportion of the membrane to create a seal with the rim whilesimultaneously heating the ribs. The heated ribs conform to the surfaceof the membrane.

U.S. Pat. No. 4,448,345 to Helms shows a composite lid structure for acontainer. A molded upper ring member is combined with a flexiblelaminate panel positioned on the underside of the ring member thatcloses the center area of the ring. An adhesive is provided under thepanel and below the ring to temporarily secure the panel duringassembly. An RF source is used to heat metal particles in the panel toform a seal with the rim of the container. The lid (ring and panelcombination) may be removed from the container, leaving the membranesealed to the rim.

SUMMARY OF THE INVENTION

A container and closure assembly is provided. The container defines aninternal volume by one or more walls and an opening therein for accessto the product retained within the container. A projecting rim surroundsthe opening and includes a rim sealing surface. The closure is providedfor covering the container opening. The closure is formed from a supportring, dimensioned to surround the rim of the container, and a sealingmembrane. The ring includes a ring sealing surface positioned concentricwith the rim sealing surface when the ring is positioned to surround thecontainer rim. The membrane is sealed to the rim sealing surface andfurther to the ring sealing surface. The seal of the membrane to the rimsealing surface is separable upon removal of the ring from its positionsurrounding the rim of the container, while the seal of the membrane tothe ring remains in place upon ring removal.

In a further aspect of the assembly, the concentric positioned ring andrim sealing surfaces are positioned substantially in the same plane.Further, it is preferred that the membrane is heat sealed to the ringsealing surface and the rim sealing surface.

In a still further aspect of the assembly, a lifting tab may beprovided, framing a projection on the periphery of the ring. Preferably,the container rim extends outward, transverse to the opening defined inthe container.

In a further aspect of the assembly, the ring may comprise a skirtportion extending substantially transverse to the ring sealing surface.A retaining ridge or similar resilient attachment means may be formed onan inwardly facing surface of the skirt portion. The retaining ridge ispreferably formed for engaging the rim of the container and retainingthe ring and sealed membrane on the rim.

The container is preferably formed from a thermoplastic material, as isthe ring structure. The container and ring are preferably injectionmolded. The container and ring may be separately formed or may beintegrally molded, with a frangible connection there between.

A method of sealing a closure to a container is also contemplated by thepresent disclosure. The method of sealing the container is defined byproviding a container having an interval volume, an opening therein foraccess to the internal volume, a projecting rim surrounding the opening,and the rim having a sealing surface. A support ring is further providedthat is dimensioned to surround the rim of the container, and ispreferably concentric with the rim. The ring is provided with a ringsealing surface. The ring sealing surface is positioned to surround therim sealing surface, with the ring sealing surface preferably positionedin substantially the same plane as the rim sealing surface when the ringsurrounds the rim. A membrane is provided having a surface areacorresponding to the area defined by the support ring. The membrane ispositioned to contact the rim sealing surface and the ring sealingsurface and then sealed there to. The seal of the membrane to the rimsealing surface is formed to be separable upon removal of the ring fromits position surrounding the rim. The seal of the membrane to the ringremains in place upon ring removal, creating a closure lid that may berepeatedly positioned on and removed from the rim of the container.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, there is shown in thedrawings one or more forms that are presently preferred; it beingunderstood that the invention is not limited to the precise arrangementsand instrumentalities shown,

FIG. 1 is a perspective view of a container and closure assembly, in aform contemplated by the present disclosure.

FIG. 2 is a top view of the closure as shown in FIG. 1, with containerportions shown in phantom.

FIG. 3 is an exploded perspective view of the constituent parts of thecontainer and closure assembly.

FIG. 4 is an enlarged, partial cross sectional view of constituent partsof the container and closure assembly prior to sealing of the closure.

FIG. 5 is an enlarged, partial cross sectional view of constituent partsof the container and closure assembly after sealing of the closure.

FIG. 6 is an enlarged, partial cross sectional view of constituent partsof the container and closure assembly prior after removal of the sealbetween the closure and the container.

FIG. 7 is an enlarged, partial cross sectional view of constituent partsof the container and closure assembly after reclosing the container.

DETAILED DESCRIPTION

Referring now to the drawings, where like numerals identify likeelements, there is shown in FIG. 1 an assembly forming a sealed package,which is generally referred to by the numeral 10. In FIG. 1, theassembly 10 is composed of a container 12 and a closure 14, which mayalso be referred to as—among other things—an overcap or lid. The closure14 is positioned on the top end of the container 12 and is secured to arim 18 surrounding the opening into the container 12. An opening tab 16projects from the peripheral edge of the closure 14 for ease of removingthe closure 14 from the container 12. In FIG. 2, it can be seen that theclosure 14 surrounds the container rim 18 (shown in phantom).

In FIG. 3, the constituent parts of the assembly 10 are shown. Theclosure 14 is formed by a ring structure 20 and membrane seal 22. Thering 20 is preferably dimensioned such that a central opening 24 in thering 20 has an inside dimension generally the same as the outsidedimension of rim 18 of the container 12. The membrane 22 is dimensionedto extend across the area of the central opening 24 and to also overlapwith the upper surface of the ring 20. Hence, the membrane 22 alsocovers the container opening 26 and rim 18 (as shown in FIGS. 1 and 2).

In the partial cross section of FIG. 4 there is shown a portion of thecontainer rim 18 and the ring 20, prior to the attachment of themembrane 22 to the complete the assembly. The rim 18 as illustrated isdefined at the top of the sidewall 28 of the container 12. The rim 18 isintegrally formed with the sidewall 28 and includes an inside surface30, a top surface 32 and a radially outward projecting flange 34. Theflange 34 includes a rounded bead portion 36 and an undercut surface 38.The undercut surface 38 joins with the outside surface of the sidewall28.

The present form of the rim 18 and container 12 are provided forillustration purposes. Other forms of containers and rims are known andmay be used along with the closure contemplated herein. As anon-limiting example, the container may have a shape other than a roundbody and opening, as illustrated. The container shape may be oval,square, rectangular, oblong, etc. In addition, the shapes of the openingand container may differ. Further, the rim of the container may includedvarious flat, pointed, undulating, or rounded (concave, convex or both)surfaces. Generally, the rim is contemplated to be defined by asubstantially continuous surface that surrounds the container opening.Preferably, the rim is formed on a projection from the container body.The top surface of the rim is sometimes referred to as a chime andgenerally faces outwardly, transverse to the area of the containeropening. The top surface may further be formed as a radial inwardlyprojected flange or surface.

In FIG. 4, the ring 20 is positioned concentric with the rim 18. Thering 20 includes a top surface 40, an inward surface 42, a retainingridge 44 and an outside periphery 46. The top surface 40 of the ring 20is shown to be positioned in the same plane as the top or chime surface32 of the container rim 18. The inside surface 42 of the ring 20 facesradially inward and is shown to be in contact with the rounded bead 36on the flange 34. The retaining ridge 44 also faces inwardly, having aportion underneath the bead 36. In the initial step, the membrane 22 ispositioned above the planer top surface 32 of the rim 18 and the topsurface 40 of the concentric ring 20.

In FIG. 5, the membrane 22 is shown as being sealed to both the rim 18of the container 12 and the ring 20. A sealing tool 62 is moveddownwardly (arrow 60) towards the top surface 52 of the membrane 22. Thesealing tool form a rim seal 48 inward of a ring seal 50 due to therelative positioning of the rim 18 and ring 20. Preferably, the twoseals 48, 50 are heat seals created by the application of pressure andheat by the sealing tool 62 against the membrane 22, with the pressuredirected downwardly towards the top surface 32 of the rim 18 and the topsurface 40 of the ring 20. The two seals 48, 50 are preferably formedsimultaneously. The sealing tool 62 preferably includes a sealingsurface that conforms to the contours of the two surfaces 32, 40. Aseparate support (not shown) may be provided to position the containerand ring during the application of the sealing force/pressure. Inaddition, the membrane may be preformed to conform to the outline of thering (with or without including the area of the lift tab extension). Atensioning force may also be applied to the membrane, transverse to thesealing force.

The strength of each of the two seals 48, 50 is preferably different soas to create a peelable or separable seal between the rim 18 andmembrane 22 and a more permanent seal between the membrane 22 and ring20. Generally, upon sealing the membrane 22 to the rim, the container 12is hermetically sealed, protecting the product retained within theinterior volume. In addition, the sealing of the membrane 22 to the ring20 creates a closure 14 for the container 12.

In FIG. 6, the closure 14, which is the combination of the ring 20 andmembrane 22, is shown as separated from the rim 18 of the container 12.The separation may be cause by a lifting force 56 applied to the ring20, such as an upward force of the tab 16 (as shown in FIGS. 1-3). Thelifting force 56 on the ring 20 is contemplated to separate the peelableseal (48) connecting the rim 18 to the membrane 22, with the seal 50between the ring 20 and membrane remaining in place. The lifting force56 is also contemplated to move the retaining ridge 44 around the bead36 of flange 34, resulting from the flexibility of the ring 20 and itsassociated material. The ridge 44 separation is contemplated to besimilar to the removal of a typical overcap from a container.

In FIG. 7, the closure 14 is shown in a covering position with thecontainer rim 18. The membrane 22 and ring 20 remain sealed to oneanother and create a composite structure. The closure 14 acts like atypical overcap and may be replaced on the rim 18 for closing thecontainer 12. A closure force 58 is directed to the ring portion 20 andserves to overcome the resistance of the ridge 44 and bead 36, due totheir dimensional relationship. The ring 20 material is contemplated toflex to permits the ridge 44 to move around the bead 36 of the rim 18.Once the closure 14 is positioned on the rim 18, the membrane 22 ispositioned adjacent the rim top surface 32, with the ring 20concentrically positioned.

The seal 50 between the ring 20 and the membrane 22 remains in place inthe creation of the closure 14. The seal (48) between the membrane 22and rim 18 has previously been removed. Hence, the replacement of theclosure 14 on the rim is no longer a hermetic seal, but provides a(temporary) freshness closure for the container contents. Further, theclosure 14 may be removed (FIG. 6) and replaced (FIG. 7) as often asdesired.

The assembly 10 and its method of formation may create a number ofadvantages. The creation of a composite closure, formed from a ring andmembrane, is contemplated to create a relatively light weight structurethat has a reduced production cost, as compared to a molded overcap witha central body also part of the molded element. Further, the structuremay be formed with a hermetic seal using the membrane that also formsthe closure lid.

In forming a seal for the container, it is preferred that the sealingsurfaces be aligned adjacent one another, with both facing upwardly fromthe top surfaces (32, 40) of the rim (18) and ring (20). The similarlyfacing sealing surfaces provide for forming the two seals in a singlestep, using a single sealing tool structure. The two surfaces may bepositioned in a single plane. Variations in the form of the tool or thesealing process may permit formation at differing surface levels. Forexample, small variations in the position of the two sealing surfacesmay result in an advantageous difference in sealing force applied.Hence, a relatively greater heat and/or pressure on the ring seal mayresult in a stronger seal as compared to the seal formed with thecontainer rim. Such variation are intended in the creation of the rimseal, which is contemplated to be peelable or otherwise breakable whilethe ring seal is contemplated to be permanent so as to form the reusableclosure lid. In the figures, the rim seal (48) is shown as being widerthan the ring seal (50). However, such is not a fixed requirement forthe formation and use of the assembly. Other variations in the size ofthe seal, the amount of heat and pressure applied, and the materialsinvolved in creating a seal are contemplated.

The materials used to form the rim of the container, the container body,the ring and the membrane may vary without departing from the advantagescontemplated by the structure specifically described herein. As shown,the rim is integrally formed with the container body and is preferablyformed by an injection molding process. The rim may be separatelyattached to the container and may have forms different from those shown.The rim and ring may also be integrally formed with a frangibleconnection provided between the two parts. A coating or other adhesivemay be used to create or assist in creating the various seals betweenthe rim, ring and membrane.

The membrane may have a variety of forms. For example, the membrane maybe composed of a laminate material or a single layer of a flexibleplastic. A foil material may also be utilized, with a desired coatingapplied on the inside surface for forming the heat seal with the rim andring structures. Alternatively, the membrane may be formed ofpolyethylene or other flexible plastic. The container may be injectionmolded from a polypropylene material. The ring may also be molded usingpolypropylene or another moldable plastic. The container may be formedfrom a composite material, incorporating one or more layers of paper.The container may include a rolled rim or a separately attached rimstructure, formed of metal, plastic or a composite structure. A coatingmay be applied to the exposed top surface of the rim and/or the ring toassist in the formation of the membrane seal.

In the drawings and specification, there has been set forth one or moreembodiments of the invention and, although specific terms are employed,these terms are used in a generic and descriptive sense only and not forpurposes of limitation. The scope of the invention is set forth in thefollowing claims.

1. A container and closure assembly, comprising: a container having avolume defined by one or more walls and an opening therein for access tothe defined volume, the opening defined by a projecting rim surroundingthe opening, the rim having a rim sealing surface, and a closure forcovering the container opening, the closure comprising a support ringdimensioned to surround the rim of the container, the ring having a ringsealing surface, the ring sealing surface positioned concentric with therim sealing surface when the ring is positioned to surround the rim, anda membrane having a surface area defined by the support ring, themembrane sealed to the rim sealing surface and sealed to the ringsealing surface, wherein the seal of the membrane to the rim sealingsurface is separable upon removal of the ring from its positionsurrounding the rim of the container, while the seal of the membrane tothe ring remains in place upon ring removal.
 2. The container andclosure assembly as in claim 1 wherein the concentrically positionedring sealing surface and rim sealing surface are positionedsubstantially in the same plane.
 3. The container and closure assemblyas in claim 1 wherein the membrane and the ring sealing surface are heatsealed to one another.
 4. The container and closure assembly as in claim1 wherein the membrane and the rim sealing surface are heat sealed toone another.
 5. The container and closure assembly as in claim 1 whereinthe closure further comprises a lifting tab projecting from theperiphery of the ring.
 6. The container and closure assembly as in claim1 wherein the container rim extends outwardly from the projecting rimand the opening defined thereby.
 7. The container and closure assemblyas in claim 1 wherein the ring further comprises a skirt portion, theskirt portion extending substantially transverse to the ring sealingsurface.
 8. The container and closure assembly as in claim 7 wherein thering further comprises a retaining ridge formed on an inwardly facingsurface of the skirt portion, the retaining ridge formed for engagingthe container and retaining the ring and sealed membrane on the rim. 9.The container and closure assembly as in claim 1 wherein the containeris formed from a thermoplastic material.
 10. The container and closureassembly as in claim 1 wherein the container is injection molded. 11.The container and closure assembly as in claim 1 wherein the ring ismolded from a thermoplastic material.
 12. The container and closureassembly as in claim 1 wherein the ring and container rim are separatelyformed.
 13. The container and closure assembly as in claim 1 wherein thering and container rim are integrally molded and frangibly connected toone another.
 14. A container and closure assembly, comprising: acontainer for retaining a product, the container including an openingfor access to the retained product, a projecting rim surrounding theopening, and an outwardly facing rim sealing surface, and a closure forcovering the container opening, the closure comprising a support ringdimensioned to surround the rim of the container, the ring having a ringsealing surface positioned concentric with the rim sealing surface whenthe ring surrounds the rim, and a flexible membrane fixedly sealed tothe rim sealing surface and separately sealed to the ring sealingsurface, the separate seal being peelable from the rim upon applicationof a lifting force, wherein the closure is removable from thecontainers, with removing the closure separating the seal between themembrane and the rim sealing surface, and wherein the closure may bereplaced onto the container rim for releasably covering the opening. 15.The container and closure assembly as in claim 14 wherein theconcentrically positioned ring sealing surface and rim sealing surfaceare positioned substantially in the same plane.
 16. The container andclosure assembly as in claim 14 wherein the ring further comprises alifting tab projecting from the periphery.
 17. The container and closureassembly as in claim 14 wherein the ring further comprises a skirtportion, the skirt portion extending substantially transverse to thering sealing surface.
 18. The container and closure assembly as in claim17 wherein the ring further comprises a retaining ridge formed on aninwardly facing surface of the skirt portion, the retaining ridge formedfor engaging the rim of the container and retaining the ring and sealedmembrane on the rim.
 19. A method of sealing a closure to a container,the method comprising the steps of: providing a container having avolume defined by one or more walls, an opening therein for access tothe defined volume, a projecting rim surrounding the opening, and a rimsealing surface, providing a support ring dimensioned to surround therim of the container, the ring having a ring sealing surface,positioning the ring sealing surface to surround the rim sealingsurface, wherein the ring sealing surface is adjacent the rim sealingsurface when the ring surrounds the rim, providing a membrane having asurface area corresponding to the inward area defined by the supportring, positioning the membrane in contact with the rim sealing surfaceand the ring sealing surface, and sealing the membrane to the rimsealing surface and the ring sealing surface, wherein the seal of themembrane to the rim sealing surface is separable upon removal of thering from its position surrounding the rim of the container, and theseal of the membrane to the ring remains in place upon ring removal. 20.The method as in claim 19 further comprising the step of positioning theconcentrically ring sealing surface and rim sealing surface insubstantially in the same plane.
 21. The method as in claim 19 whereinthe sealing of the membrane to the ring sealing surface and to the rimsealing surface results from a heat sealing operation.
 22. The method asin claim 19 further comprising the step of providing a lifting tabprojecting from the periphery of the ring.
 23. The method as in claim 19wherein the container rim extends radially outwardly from the containeropening.
 24. The method as in claim 19 wherein the support ring furthercomprises a skirt portion, the skirt portion extending substantiallytransverse to the ring sealing surface.
 25. The method as in claim 24wherein the support ring further comprises a retaining ridge formed onan inwardly facing surface of the skirt portion, and further comprisingthe step of engaging the ridge with the rim of the container forresiliently retaining the ring on the rim.
 26. The method as in claim 19wherein the container is formed from a thermoplastic material.
 27. Themethod as in claim 26 wherein the container is injection molded.
 28. Themethod as in claim 27 wherein the support ring is molded from athermoplastic material.
 29. The method as in claim 28 wherein thesupport ring and container rim are separately formed.